Safety, tolerability and immunogenicity of VAQTA given concomitantly versus nonconcomitantly with other pediatric vaccines in healthy 12-month-old children.

BACKGROUND: The objective of this study is to assess whether hepatitis A vaccine is immunogenic and well tolerated when administered to 12-month-old children alone or concomitantly with other routinely administered pediatric vaccines. METHODS: Six hundred seventeen healthy 12-month-old children were randomized to receive dose 1 of hepatitis A vaccine given alone or concomitantly with measles-mumps-rubella vaccine and varicella vaccine and dose 2 of hepatitis A vaccine given alone or concomitantly with diphtheria-tetanus-acellular pertussis vaccine and optionally with oral or inactivated poliovirus vaccine. Participants were followed for clinical adverse experiences and serologic responses to all vaccine antigens. Antibody responses were compared with historical controls for some indices. RESULTS: The safety profile was generally comparable whether hepatitis A vaccine was administered alone or concomitantly with other vaccines. When administered alone, the hepatitis A seropositivity rate was 98.3% and 100% for dose 1 and dose 2, respectively, and after dose 2 was similar to historical rates and the geometric mean titers were similar between initially seropositive and initially seronegative subjects (6207 and 6810 mIU/mL, respectively). After concomitant administration with hepatitis A vaccine, antibody responses to measles, mumps, rubella, diphtheria, tetanus and filamentous hemagglutinin (98.8%, 99.6%, 100%, 98.6%, 100% and 83.3%, respectively) were similar to historical controls and response to poliovirus was demonstrated, but immune responses to varicella zoster virus (79%) and pertussis toxoid (76%) were inferior to historical controls. CONCLUSIONS: Hepatitis A vaccine is highly immunogenic and generally well tolerated when administered to healthy children as young as 12 months of age regardless of initial hepatitis A serostatus and can be administered concomitantly with measles-mumps-rubella vaccine and oral or inactivated poliovirus vaccine.

Safety and immunogenicity of an inactivated hepatitis A vaccine among HIV-infected subjects.

BACKGROUND: Hepatitis A is a major health risk for many human immunodeficiency virus (HIV)-infected individuals. Vaccination is a potentially attractive measure to reduce the incidence of hepatitis A among this population, but data on its safety and immunogenicity are incomplete. METHODS: Ninety HIV-uninfected adults received an inactivated hepatitis A vaccine (VAQTA; Merck), and 90 HIV-infected subjects were randomized, in double-blind fashion, to receive either the vaccine or placebo. The HIV-infected subjects were stratified by CD4 cell count, with 45 subjects having CD4 cell counts of > or =300 cells/mm3 and 45 subjects having CD4 cell counts of <300 cells/mm3. Vaccine was given at weeks 0 and 24 of the study.Results. Seroconversion rates at week 28 of the study were 94% among the HIV-infected subjects and 100% among the HIV-uninfected control subjects. HIV-infected subjects with CD4 cell counts of <300 cells/mm3 had a seroconversion rate of 87%, and HIV-infected subjects with CD4 cell counts of > or =300 cells/mm3 had a seroconversion rate of 100%. The vaccine was generally well tolerated, and no adverse effect on either HIV load or CD4 cell count was found. CONCLUSION: Hepatitis A vaccine was both immunogenic and safe among HIV-infected subjects.

Analysis of safety data in children after receiving two doses of ProQuad® (MMRV).

BACKGROUND: In randomized clinical studies, over 11,800 children, 12 months to 6 years of age, were administered ProQuad(®), a combination measles, mumps, rubella, and varicella vaccine (MMRV). This paper describes the safety following a 2-dose regimen of MMRV administered to children in the second year of life. METHODS: Safety data from five clinical studies were combined for all children who were scheduled to receive two doses of MMRV ∼3-6 months apart. All vaccinated children were followed for safety following each dose of MMRV. RESULTS: Of 3112 children who received a first dose of MMRV, 2780 (89.3%) received a second dose of MMRV. Overall, 70.5% and 57.7% of children reported ≥1 adverse experiences following first and second doses of MMRV, respectively. Injection-site redness was statistically significantly higher postdose 2 than postdose 1, while injection-site pain/tenderness was statistically significantly higher postdose 1 compared to postdose 2. Rashes were statistically significantly lower postdose 2 compared to postdose 1. Ten febrile seizures (8 postdose 1, 2 postdose 2) were reported following MMRV vaccination. The incidence of febrile seizures postdose 1 of MMRV was 0.26% (8/3019) compared to 0.07% (2/2695) postdose 2 of MMRV. CONCLUSIONS: Administration of two doses of MMRV has an acceptable safety profile in children 12 to 23 months of age. There is a small increase in the risk of febrile seizures following the first dose of MMRV as compared to the component vaccines, but the risk for any individual child is relatively low.